Comp. by: LElumalai Stage : Revises1 ChapterID: 9781405132879_4_C Date:31/3/09
Time:21:45:53 Filepath://ppdys1108/BlackwellCup/00_Blackwell/00_3B2/Gregory-
9781405132879/appln/3B2/revises/9781405132879_4_C.3d
for quantitative analysis. This is vital, as the
procedures used to calibrate models do not
permit exact analytical solutions as in standard
regression, but require an iterative approach,
which can be computationally expensive. kjSuggested reading
Agresti (2002); Power and Xie (2000); Wrigley
(1985b).cellular automata Models of spatial phe-
nomena, usually comprising arastergrid of
cells, each of which has a value representing
its present ‘state’ on a variable of interest.
algorithmswith theoretically derived rules
are applied to the initial system configuration
to simulate changes. Run many times (each
run is termed a ‘generation’), the algorithm
produces an evolving pattern. A classic
example is the well-known ‘game of life’, in
which all cells are initially identified as either
alive or dead (Conway, 1970); its algorithm’s
rules specify that, for example, if any cell has
fewer than two live neighbours, it too will die.
Cellular automata have been used for sev-
eral decades inhuman geographyto simulate
spatial patterns and change – as in Torsten
Ha ̈gerstrand’s original work on thediffusion
of innovations (see Morrill, 2005).
Developments in computer technology, espe-
ciallygeographic information systemsand
geocomputation, have enabled large-scale
use of cellular automata models to simulate
a wide range of environmental and other
geographies (cf.agent-based modelling).rjcensus An enumeration, usually under-
taken within thestate apparatus, to provide
needed data forstatepurposes. The Latin
word census translates as ‘tax’, giving a clear
indication of the purpose of such enumer-
ations, the first of which are believed to take
been taken in Egypt some 3,000 years ago.
Manyad hoccensuses were taken before the
nineteenth century – as with the 1086
Domesday bookin England. Since then, an
increasing number of countries have con-
ducted regular (usually decennial) censuses
as part of the development of statistics to
inform the ever-widening range of government
decision-making (Cullen, 1975). Censuses of
population and housing are the most common,
but separate censuses of, for example, agricul-
ture, construction, (local) governments, manu-
facturing, mining and retailing have been held.
A few countries – mainly in Scandinavia – have
replaced censuses by continuously updated,
geocodedpopulation registers.Censuses are constitutionally mandated in
some countries. In the USA, for example,
Section Two of the First Article states that
‘Representatives and direct taxes shall be
apportioned among the several states ...
according to their respective numbers’: the
first census was to be conducted within three
years of the constitution’s acceptance, and
‘within every subsequent term of ten years’.
They have been conducted decennially since
1790, and their findings have sometimes been
hotly disputed because of their implications –
as with the allocation of seats to the US House
of Representatives after the 2000 census
(Johnston, 2002: on the history of the US
Census, see Eckler, 1972).
Although the primary role of a census is to
collect factual information to informpublic
policy– both current and future (such as
population projections) – nevertheless they
cannot be considered ‘neutral’ tools. The data
that they collect all refer to categories (occupa-
tionalclass,ethnicityetc.) that are social
constructions, whose nature is determined by
some theory of what should be measured, and
how – as with the main ethnicity categories now
used in the US Census (White; Black
or African-American; American Indian and
Alaskan Native; Asian; Native Hawaiian and
Other Pacific Islander; Hispanic or Latino
Origin) which dominate discourse aboutrace
and ethnicity there (Robbin, 2000; Yanow,
2002). Early US censuses generated consider-
able conflict between northern and southern
states over counting slaves: southerners wanted
to count them, because they would boost their
entitlements to federal revenues and represen-
tation; northerners opposed toslaverywere
against. Eventually a compromise was reached,
and slaves were counted as three-fifths only of
‘all other persons’ until after the Civil War.
‘Indians not taxed’ were excluded entirely until- A similar situation obtained in Australia,
whose original constitution – passed in 1900 –
included ‘In reckoning the numbers of the
people. .. aboriginal natives shall not be
counted’. This remained the case until 1967,
when voters overwhelmingly approved (91 per
cent in favour: voting is compulsory in
Australia) a referendum including the require-
ment that Aboriginals ‘be counted in reckoning
the population’.
Just as there is a politics and a sociology of
official statistics, including censuses (on which
see several chapters in Alonso and Starr,
1987), so there is also a politics and sociology
of their use. Data can be deployed in a variety
of ways to sustain particular cases, including
Gregory / The Dictionary of Human Geography 9781405132879_4_C Final Proof page 74 31.3.2009 9:45pmCELLULAR AUTOMATA